Display screen or portion thereof with a graphical user interface



The FIGURE is a front view of a display screen or portion thereof with agraphical user interface showing our new design.

The heavy broken lines shown as part of the icon in the lower left formspart of the claimed design. The other, fine broken line showing of adisplay screen or portion thereof with a graphical user interface isincluded for the purpose of showing portions of the article which formno part of the claim.

CLAIM We claim the ornamental design for a display screen or portionthereof with a graphical user interface, as shown and described.